surface chemistry exercise

https://drive.google.com/file/d/0B37pGFUy5hT7NjZlZU9XSFh2RzQ/view?usp=sharing

1.	Why is it essential to wash the precipitate with water before estimating it quantitatively?	1
2.	Why are powdered substances more effective adsorbents than their crystalline forms?	1
3.	Why is adsorption always exothermic?	1
4.	Write any two characteristics of Chemisorption.	2
5.	A colloidal solution of AgI is prepared by 2 different methods as shown: (i) What is the charge of AgI colloidal particles in the two test tubes (A) and (B)? (ii) Give reasons for the origin of charge	2
6.	Why is it necessary to remove CO when ammonia is obtained by Haber’s process?  Why is the ester hydrolysis slow in the beginning and becomes faster after sometime?  Why A delta is formed at the point where the river enters the sea.	2
7.	A graph between log(x/m) and log p is a straight line at angle of 450 with intercept on the y-axis( log k ) equal to 0.301. Calculate the amount of the gas adsorbed per gram of the adsorbent under a pressure of 0.4 Atmosphere	2
8.		2
9.	(i)What do you understand by activation of adsorbent? How is it achieved?  (ii)Critical temperatures of N2, CO, CH4 are 126, 134, and 110 K respectively. Arrange them in increasing order of adsorption on the surface of activated charcoal?	2
10.	What is an adsorption isotherm? Describe Freundlich adsorption isotherm.	3
11.	What is the difference between multimolecular and macromolecular colloids? Give one example of each. How are associated colloids different from these two types of colloids?	3
12.	Explain what is observed (i) When a beam of light is passed through a colloidal sol. (ii) An electrolyte, NaCl is added to hydrated ferric oxide sol. (iii) Electric current is passed through a colloidal sol?	3
13.	(i)What are emulsions? What are their different types? Give example of each type. (ii)What is demulsification? Name two demulsifiers. (iiii) Which of the following is most effective in coagulating Fe(OH)3 sol and why? (i)            KCl; (ii) FeCl3; (iii) Na2SO4; (iv) K3[Fe(CH)6]	3
14.	: Explain the following terms: (i) Electrophoresis (ii) Coagulation (iii) Dialysis (iv) Tyndall effect	3